Foil tank



FIG. 1 is a top perspective view of a foil tank;

FIG. 2 is a front elevational view thereof, the opposite right and left side not shown is a mirror image thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof. 

CLAIM The ornamental design for a foil tank, as shown and described. 